Bulk carbonated beverage containers, and specifically beer kegs, are commonly in the nature of returnable containers. That is, after the contents are dispensed, the container is returned for reuse.
The use of non-returnable beer kegs has been proposed for several reasons, including the elimination of the expenses and difficulties in returning the empty reusable kegs, the avoidance of the necessity of clean and resterilize the kegs prior to reuse, and a substantial reduction in the cost of the individual kegs which, as a single-use item, will be subjected to far less handling and structural abuse as compared to the conventinal returnable keg.
While several attempts have been made to produce a viable non-returnable keg of sufficient structural integrity and practical low cost to both secure the product and make it practical to dispose of the keg after a single use, such attempts have met with little success.
Two examples of existing non-returnable beer kegs include a keg of all epoxy coated steel, and a bag consisting of a polyethylene terephthalates bottle reinforced with an external paper tube. However, while the structural integrity of such products are generally adequate for a single use item, the cost of the kegs, as compared to the cost of a returnable keg, is too great to be economically feasible.
Basically, not only must a non-returnable or single-use beer keg be inexpensive, because of the particular nature of the goods to be stored therein, it must be liquid-tight, capable of sustaining internal pressure of at least 60 psi, and possibly as great as 120 psi, without distortion or rupture, and must be capable of resisting damage from external forces during the rough handling to which such kegs are frequently subjected.